Inverted Ligand Field in a Pentanuclear Bow Tie Au/Fe Carbonyl Cluster

Gold chemistry has experienced in the last decades exponential attention for a wide spectrum of chemical applications, but the +3 oxidation state, traditionally assigned to gold, remains somewhat questionable. Herein, we present a detailed analysis of the electronic structure of the pentanuclear bow tie Au/Fe carbonyl cluster [Au{η2-Fe2(CO)8}2]- together with its two one-electron reversible reductions. A new interpretation of the bonding pattern is provided with the help of inverted ligand field theory. The classical view of a central gold(III) interacting with two [Fe2(CO)8]2- units is replaced by Au(I), with a d10 gold configuration, with two interacting [Fe2(CO)8]- fragments. A d10 configuration for the gold center in the compound [Au{η2-Fe2(CO)8}2]- is confirmed by the LUMO orbital composition, which is mainly localized on the iron carbonyl fragments rather than on a d gold orbital, as expected for a d8 configuration. Upon one-electron stepwise reduction, the spectroelectrochemical measurements show a progressive red shift in the carbonyl stretching, in agreement with the increased population of the LUMO centered on the iron units. Such a trend is also confirmed by the X-ray structure of the direduced compound [Au{η1-Fe2(CO)8}{η2-Fe2(CO)6(μ-CO)2}]3-, featuring the cleavage of one Au-Fe bond

Electron transfer and CO addition to polynitrido cobalt carbonyl clusters: Parallel pathways for conversion of the [Co10N2(CO)(19)](4-) anion to the novel [Co11N2(CO)(21)](3-) anion

The redox aptitude of the dinitrido anion [Co10N2(CO)19]4- has been tested from both chemical and electrochemical points of view, together with its reactivity toward CO that induces disproportionation. In any case, through a remarkable overlapping of intermediate steps, the new anion [Co11N2(CO)21]3- (4) is eventually obtained. A detailed study of the pathways to 4 allowed the identification of three labile intermediates by their characteristic IR spectra as well as their electrochemical and paramagnetic properties. The unprecedented structure of trianion 4 has been studied in details in two different crystalline salts

Endohedral Metallofullerenes Today: More and More Versatile Ships in Multiform Bottles-Electrochemistry of X-Ray Characterized MonometallofullerenesAdvances in Organometallic Chemistry and Catalysis

Endohedral Metallofullerenes Today: More and More Versatile Ships in Multiform Bottles—Electrochemistry of X-Ray Characterized Monometallofullerene

The competition between chemistry and biology in assembling iron-sulfur derivatives. Molecular structures and electrochemistry. Part IV. [Fe3S4](SγCys)3 proteins

Iron-sulfur clusters are ubiquitous and evolutionary ancient prosthetic groups which participate in electron transfer processes of crucial biological interest. In view of such a significant aspect we aimed to update their structure and electrochemistry. In this picture, after having reviewed Fe(SγCys)4 rubredoxins (Coord. Chem. Rev., 257 (2013) 1777–1805), [Fe2S2](SγCys)4 ferredoxins (Coord. Chem. Rev., 280 (2016) 50–83) and Rieske [Fe2S2](SγCys)2(His)2 ferredoxins (Coord. Chem. Rev., 306 (2016) 420–442), we will now deal with [3Fe-4S] proteins. As usual, we will also deal with the synthetic analogues of the related iron-sulfur clusters

Inorganic Electrochemistry. Theory, Practice and Application, 2nd Edition

In order to understand the basic aspects of an electrochemical investigation on inorganic molecules (in its widest meaning, of any molecule which contains at least one metal centre) it must be taken into account that in these molecules the metal-ligand bonds are of the prevailingly covalent type. Since electrochemical techniques allow you to add or remove electrons in a controlled manner, it is conceivable that the addition or removal of electrons inside these molecules can lead to the formation of new bonds or to the breakage of existing bonds. The main aim of this book is to study the effects of such electron addition and removal processes on the molecular frames. The second edition of this classic book has been fully revised and updated and is a straightforward, logical introduction to electrochemical investigations for inorganic chemists. All chapters have been rewritten with new material including: - the addition of reactivity with nitric oxide to the chapter on the reactivity of metal complexes with small molecules - thiolate-protected gold nanoclusters has been added to the chapter on metal-sulfur and metal-carbonyl clusters - a new chapter on the digital simulation of electrochemical responses - a new chapter on the theoretical calculations to explain the nature of the electrochemical activity of metal complexes - new chapters on spectroelectrochemistry and electrochemiluminescence. The book covers every aspect of inorganic electrochemistry - the introduction is followed by chapters on the basic aspects of electrochemistry followed by practical and applicative aspects and ends with full appendices. It is probably the only publication with a simple approach to electrochemical aspects of the topics in inorganic chemistry. Bridging the gap between undergraduate and research-level electrochemistry books, this publication will be a welcome addition to the literature of inorganic chemists. It will also be particularly useful to final year students in chemistry and as background reading for graduates and researchers without adequate electrochemical knowledge to become active in the discipline or who want to collaborate with electrochemists

Mononuclear Metallacarboranes of Groups 6-10 Metals. Analogues of Metallocenes: Electrochemical and X-Ray Structural Aspects

Metallacarboranes containing carborane ligands possessing a pentagonal open face can coordinate metal atoms in a η5-manner quite similar to the cyclopentadienyl monoanion, thus affording metallocene analogues. By virtue of such an analogy, their electron transfer aptitude plays an important role in their physico-chemical characterisation. We review such an aspect, also providing evidence for the structural consequences of their electron transfer processes. At variance with metallocenes, electrochemical investigations on the metallacarboranes have not yet become a routine tool to search for their potential application in fields which require electronic mobility